A waterproof sheet comprising a vinyl chloride-based resin composition which comprises 100 parts by weight of a vinyl chloride-based resin (A), 5 to 100 parts by weight of a plasticizer (B), 0.05 to 5 parts by weight of a hindered amine compound (C) represented by the following general formula (1), and 0.05 to 5 parts by weight of a benzotriazole-based ultraviolet light absorber (D) represented by the general formula (II): ##STR00001## wherein R.sup.1 and R.sup.2 represent each independently an alkyl group having 4 to 20 carbon atoms or a cycloalkyl group having 5 to 6 carbon atoms; ##STR00002## wherein R.sup.3 represents an alkyl group having 1 to 12 carbon atoms.